1. Field of the Invention
The present invention relates to armor materials, and particularly non-transparent armor materials. The present invention most particularly relates to armor materials comprising polycarbonate materials in combination with ceramic.
2. Art Background
Armor materials for non-transparent applications, such as bullet proofing vehicles and buildings and the like are well-known in the art. One common arrangement of such materials is made of ceramic materials disposed within a synthetic cloth-like material sold by DuPont Corporation under the brand name Kevlar.RTM.. While such material is substantially protective and light weight, it is also very expensive.
One such arrangement was described in U.S. Pat. No. 4,633,756, which discloses a bullet-proof armor shield comprising a composite construction utilizing a ceramic armor plate disposed within layers of Kevlar material.
Another type of ceramic-containing bullet-proof armor plating is disclosed in U.S. Pat. No. 4,948,673, which discloses a multi-layer composite protective panel having layers of aluminum, polyurethane resin, a composite made up of aramid fibers embedded in a polyurethane resin, another layer of adhesive, and a plurality of ceramic tiles adhered to the outer surface by the adhesive.
Polycarbonate sheets are commonly used as bullet proof material for bullet proof glass and safety glass. These materials are typically used where transparency is a requirement of the material. Many different types of polycarbonate sheeting are usable as a bullet proof material. One form of polycarbonate sheet containing bullet proof material is described in Hall, U.S. Pat. No. 4,908,083, which discloses an impact-resistant laminate comprising polycarbonate up to 3 mm thick adhered to glass.
Molari, Jr., U.S. Pat. No. Re. 32,406, discloses a polycarbonate sheet coated with a polyurethane sheet.
Vincent, U.S. Pat. No. 4,387,129 is directed to a polyurethane adhesive material for making laminates, and specifically, one embodiment in which a laminate comprising a 1.5 mm thickness of polyurethane resin adhesive to bond two layers of 10 mm polycarbonate and another embodiment in which a 4 mm sheet is disclosed.
However, no prior art device has heretofore combined the light weight low cost of polycarbonate and polyurethane with protective, non-transparent ceramic material to form a relatively inexpensive, but light weight and effective bullet proof material.